We are using behavior-based principles to develop algorithms for flexible,
robust, and scalable multi-robot spatial formations using only local sensing
and control.

Formations, which are an instance of the general distributed multi-robot
coordination problem, have the goal of N mobile robots establishing and
maintaining some predetermined geometric shape.

We have devised a simple, general, robust, localized, behavior-based algorithm
that solves the problem for N robots each equipped with sonar, laser, camera,
and a radio link for communicating with other robots. The method uses the idea
of keeping a single friend at a desired angle (by panning the camera and
keeping the friend centered in the image), and only communicating heart-beat
messages. We also developed a general analytical method for evaluating
formations and applied it to our algorithm. We validated our algorithm in terms
of stability and robustness both in simulation and with physical robots.